EMPLOYEE BENEFIT PLANS (Details 6) (PLC, Defined Benefit Pension Plan, USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
EMPLOYEE BENEFIT PLANS
Total investments	$ 203,772	$ 180,173	$ 152,187
Employer contribution receivable	2,165	2,314
Total	205,937	182,487
Cash and cash equivalents
EMPLOYEE BENEFIT PLANS
Total investments	7,968	3,052
Equity securities: Collective Russell 3000 Equity Index Fund
EMPLOYEE BENEFIT PLANS
Total investments	79,660	74,753
Equity securities: Fidelity Spartan 500 Equity Index Fund
EMPLOYEE BENEFIT PLANS
Total investments	51,848	45,632
Fixed Income
EMPLOYEE BENEFIT PLANS
Total investments	$ 64,296	$ 56,736